The trend in the electronics industry is toward smaller devices and packages. The small size of electronic devices requires a high interconnection density. The electronic devices which require a high interconnection density, such as integrated circuits, may typically be mounted on chip carriers which in turn may be mounted to a printed circuit board. The printed circuit board contains other components which must be electrically interconnected to the integrated circuit. The chip carrier and the printed circuit board typically include corresponding patterns of conductive areas that must be electrically interconnected.
The electrical connections between a chip carrier and the printed circuit board may be made by precision soldering of the chip carrier to the printed circuit board. An alternative to soldering, is to position an interposing connector between the two surfaces to be interconnected. The interposing connector must bridge the spacing between the conductive areas to establish the interconnection.
The area used for each conductive area and the spacing between adjacent areas are desirably minimized to achieve a high interconnection density. However, as the area for each connection is reduced, irregularities between the surfaces to be interconnected become more important. For example, any surface imperfections or irregularities may require that some portions of the connector must bridge a larger or smaller spacing than other portions of the connector. A failure of the connector to bridge between all portions of the opposing surfaces results in open circuits. Irregularities may also cause unwanted compression, thereby resulting in permanent deformation and preventing reuse of an interposing connector.
The increasing complexity of modern integrated circuits requires that testing be performed to ensure reliable service. Acceptance testing and burn-in testing are highly desirable to prevent infant failures for integrated circuits. Testing requires that a repeatable and reliable connection be established between each new device under test and the testing apparatus. Since a number of integrated circuits may be mounted on a circuit board, it is also desirable that each integrated circuit be removable for troubleshooting, testing and repair even after its initial testing.
The art has attempted to produce interposing connectors that may be placed between two spaced apart opposing surfaces having a plurality of individual conductive areas. For example, U.S. Pat. No. 3,795,884 to Kotaka discloses an interposing connector block comprising a winding encapsulated in a plastic insulating material revealing exposed portions of the winding and having an axial cut therein. To conform to irregularities in the planar surfaces to be connected, the connector disclosed in Kotaka either has the winding formed of a spring-like material or the plastic housing formed of a resilient material. U.S. Pat. No. 3,638,163 to Loosme discloses a non-conductive resilient tube having a plurality of spaced conductive strips thereon.